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Date: Wed, 29 Jun 2005 10:34:02 +0200
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To: Mike Jeays <Mike.Jeays@rogers.com>
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	"freebsd-questions@FreeBSD. ORG" <freebsd-questions@freebsd.org>
Subject: Re: Shell script help
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Mike Jeays wrote:

> "man expr" to give the short answer to your first question:
> 
> As an example, x=`expr $x + 1`
> 
> 536 ~ $ x=4
> 537 ~ $ x=`expr $x + 1`
> 538 ~ $ echo $
> 
> Note the back-quotes to execute a command and return the result, and the
> need for spaces between each token in the expr command.

sh(1) is able to evaluate arithmetic expressions too, e.g.

   x=$(($x+1))



Björn